(1) Field of the Invention
The present invention relates to a tinsel wire, which is used, for example, as part of a voice coil for driving a speaker diaphragm in acoustic equipment or as an electric power supplying wire material for connecting a game machine body to a controller. Such a tinsel wire has high mechanical strength as a wire material and excellent flexing characteristics, thereby improving quality and reliability as a product.
(2) Description of the Related Art
Recently, for example, as for a speaker in acoustic equipment, a voice output having high quality, that is, a voice output having less acoustic distortion with respect to a high frequency component or high power input has been required. As for a voice coil for driving a diaphragm, a voice coil having predetermined mechanical strength and resistance values has been required.
As an electric power supplying conductor wire such as a voice coil for driving a diaphragm, there is a tinsel wire including an assembled wire formed by twisting, bundling or weaving together a desired number of element wires, in each of which a flat conductor having a rectangular shape in section is wound up around core threads. Such an electric power supplying conductor wire has a flexibility and small dynamic resistance even in a vibrating atmosphere and hardly breaks with respect to a vibration of the diaphragm (for example, see Japanese Patent Application Laid-Open No. 2004-178638).
Further, as a long aerial coated wire such as an electrically insulating wire to be provided aerially or a tube-shaped protector protecting an optical cable, there is an aerial insulating wire, an outer surface of a coating of which has a rectangular shape having, which has triangular ridge parts, of the number same as that of the sides, arranged at even intervals in a circumferential direction, by connecting the equilateral sides, the number of which is three or more, in the circumferential direction so as to inscribe it to a circle of an outer diameter thereof, wherein the number of the sides is in a range of from 6.785+0.575d−0.006732d2 to 6.949+0.8380d−0.009694d2 in a relation between the number of the sides and the outer diameter d. Such an aerial insulating wire restrains an increase of a drag coefficient so as to avoid an estimation of the drag coefficient under a condition of strong wind and rainfall in the open air, allowing the drag coefficient to decrease and preventing the outer diameter and weight of the coating from increasing (for example, see Japanese Patent Application Laid-Open No. 2005-56652).
However, when the electric power supplying conductor wire disclosed in Japanese Patent Application Laid-Open No. 2004-178638 is used, for example, as a voice coil for driving a speaker diaphragm in acoustic equipment, a mechanical strength as a wire material is not sufficient in a vibrating atmosphere, flexing characteristics are not good, a vibration amplitude of the diaphragm is deteriorated, a resonance is generated in the voice coil at a specific frequency, causing so-called a rope jumping phenomenon that a tinsel wire collides with the diaphragm and causing abnormal noise. Therefore, such an electric power supplying conductor wire lacks of performance and reliability of a speaker as a product. Further, a receiving space, in which the voice coil as the electric power supplying conductor is arranged, is not suitable for a thin designing of a speaker in a narrow arranging space between the diaphragm and a damper.
The long aerial coated wire such as an electrically insulating wire to be provided aerially or a tube-shaped protector protecting an optical cable disclosed in Japanese Patent Application Laid-Open No. 2005-56652 is for the purpose of restraining the increase of the drag coefficient under a condition of strong wind and rainfall in the open air, that is, for use in the open air, and therefore, is neither for the purpose of indoor use of the electric power supplying conductor wire nor for the purpose of use the electric power supplying conductor wire in electric or electronic equipment. Further, as for the long aerial coated wire disclosed in Japanese Patent Application Laid-Open No. 2005-56652, since a wire diameter and a weight per unit length of the insulating wire or optical cable is large in order to improve its mechanical strength as a wire to be used in the open air, therefore values thereof are significantly large after adding the size of the protector for protecting the insulating wire or optical cable. That is, the concept of the electric power supplying conductor wire itself is different from that of a wire intending an excellent dynamic following property with respect to a dynamic system such as a speaker diaphragm. An increase in the weight of a tinsel wire itself for use in a speaker causes deterioration in a sound pressure level and biased loading onto the diaphragm causing a rolling motion of the diaphragm. Furthermore, it causes a resonance in the voice coil at a specific frequency and a problem that it tends to generate so-called a rope jumping phenomenon.